That's not what I said though, I said that you get what you need by clearing the raid. If you get to boss 13 then you already have loot from bosses 1 through 12. My entire point here was to disprove the post I quoted where the person said that you had to grind for weeks in World of Warcraft to overcome an imaginary gear wall in order to clear a raid. No such wall exists. Skill walls exist, time spent walls exist, gear walls do not. Play the game like a normal person, and that is all you need.
Also, just so we're clear, a player going into a mythic raid in WoW is expected to have already cleared the previous difficulties of said raid, you don't just go straight into mythic naked, and with that assumption, they are already geared enough from clearing the previous difficulties even disregarding the gear the raid will collect by defeating bosses on mythic - which is a lot.